chiark / gitweb /
wip pager - before change to not converting until sure
authorIan Jackson <ian@liberator.relativity.greenend.org.uk>
Sat, 6 Jun 2009 11:13:38 +0000 (12:13 +0100)
committerIan Jackson <ian@liberator.relativity.greenend.org.uk>
Sat, 6 Jun 2009 11:13:38 +0000 (12:13 +0100)
pctb/ocr.h
pctb/pages.c

index d8491e6..d9a25f7 100644 (file)
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdarg.h>
+#include <time.h>
+
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <sys/time.h>
 
 
 typedef struct {
@@ -52,6 +55,10 @@ const char *get_vardir(void);
 CanonImage *file_read_image(FILE *f);
 int main_test(void);
 
+#define MAX_PAGES 100
+extern CanonImage *page_images[MAX_PAGES];
+extern int npages;
+
 
 #define DEBUG_RECTANGLES
 // #define DEBUG_OCR
index 272e5cf..66c3ad8 100644 (file)
@@ -7,15 +7,18 @@
 #include <X11/extensions/XTest.h>
 #include <X11/keysym.h>
 
-#define NUM_PAGES 25
+CanonImage *page_images[MAX_PAGES];
+int npages;
 
+static Window id;
 static Display *disp;
+static struct timeval tv_startup;
 
 static KeyCode keycode(KeySym sym) {
   return XKeysymToKeycode(disp,sym);
 }
 
-static CanonImage *screenshot_now(Window id) {
+static CanonImage *screenshot_now(void) {
   char *cmd;
   CanonImage *ci;
   int r;
@@ -30,14 +33,29 @@ static CanonImage *screenshot_now(Window id) {
   return ci;
 }
 
-static void read_pages(Window id) {
+static void screenshot_startup(void) {
+  int r;
+  disp= XOpenDisplay(0);  eassert(disp);
+  r= gettimeofday(&tv_startup,0);  eassert(!r);
+}
+
+#if 0
+static CanonImage *single_page(void) {
+  int r;
+  r= XRaiseWindow(disp, id);  eassert(r);
+  r= XSync(disp, False);  eassert(r);
+  return screenshot_now();
+}
+#endif
+
+static void raise_and_set_focus(void) {
   int r;
   XWindowAttributes attr;
   int xpos,ypos, evbase,errbase,majver,minver;
   unsigned width,height,bd,depth;
   Window dummy;
   
-  disp= XOpenDisplay(0);  eassert(disp);
+  fprintf(stderr,"PAGING raise_and_set_focus\n");
 
   r= XTestQueryExtension(disp, &evbase,&errbase,&majver,&minver);
   eassert(r==True);
@@ -55,21 +73,148 @@ static void read_pages(Window id) {
   int screen= XScreenNumberOfScreen(attr.screen);
   XTestFakeMotionEvent(disp,screen, xpos, ypos, 0);
 
-  XTestFakeButtonEvent(disp,1,1, 0);
+  XTestFakeButtonEvent(disp,1,1, 50);
   XTestFakeButtonEvent(disp,1,0, 50);
+  r= XSync(disp, False);  eassert(r);
 
-  XTestFakeKeyEvent(disp, keycode(XK_Next),1, 50);
-  XTestFakeKeyEvent(disp, keycode(XK_Next),0, 50);
-  
+  fprintf(stderr,"PAGING raise_and_set_focus done.\n");
+}
+
+static void send_key(KeySym sym) {
+  int r;
+  XTestFakeKeyEvent(disp, keycode(sym),1, 10);
+  XTestFakeKeyEvent(disp, keycode(sym),0, 10);
   r= XSync(disp, False);  eassert(r);
 }
 
+static void send_pgup(void) {
+  fprintf(stderr,"PAGING   PageUp\n");
+  send_key(XK_Prior);
+}
+static void send_pgdown(void) {
+  fprintf(stderr,"PAGING   PageDown\n");
+  send_key(XK_Next);
+}
+
+static double timestamp(void) {
+  struct timeval tv;
+  int r;
+  
+  r= gettimeofday(&tv,0);  eassert(!r);
+  return (tv.tv_sec - tv_startup.tv_sec) +
+         (tv.tv_usec - tv_startup.tv_usec) * 1e-6;
+}
+
+static double worst_snapshot= 0.050, worst_stabilise= 0.100;
+
+static void snapshot(CanonImage **output) {
+  free(*output);
+  double a= timestamp();
+  *output= screenshot_now();
+  fprintf(stderr,"PAGING   snapshot\n");
+  double b= timestamp();
+  double it_took= b-a;
+  fprintf(stderr,"PAGING   snapshot took=%f\n",it_took);
+  if (it_took > worst_snapshot)
+    worst_snapshot= it_took;
+}
+
+static void snapshot_idle(void) {
+  int r;
+  r= usleep(worst_snapshot * 1e6 * 2);
+  /* spend no more than 1/3 of our time constantly snapshotting */
+  eassert(!r);
+}
+
+static int identical(const CanonImage *a, const CanonImage *b) {
+  return !(memcmp(a,    b,    sizeof(*a)) ||
+          memcmp(a->d, b->d, a->w * a->h));
+}
+
+static void wait_for_stability(CanonImage **output,
+                              const CanonImage *previously,
+                              void (*with_keypress)(void)) {
+  CanonImage *last=0;
+  /* waits longer if we're going to return an image identical to previously
+   * if previously==0, all images are considered identical to it */
+
+  double when_started= timestamp();
+  double last_change= when_started;
+  double it_took= -1;
+
+  fprintf(stderr,"PAGING  wait_for_stability"
+         "  worst_snapshot=%f worst_stabilise=%f\n",
+         worst_snapshot, worst_stabilise);
+
+  for (;;) {
+    snapshot(output);
+    double right_now= timestamp();
+
+    if (!last || !identical(*output,last)) {
+      fprintf(stderr,"PAGING  wait_for_stability changed...\n");
+      last_change= right_now;
+      free(last); last=*output; *output=0;
+      it_took= -1;
+    } else {
+      if (it_took<0)
+       it_took= right_now - when_started;
+
+      double threshold= (worst_stabilise + worst_snapshot) * 3;
+      if (!previously || identical(*output,previously))
+       threshold *= 2;  threshold += 1.5;
+
+      double stable_for= right_now - last_change;
+      fprintf(stderr,"PAGING  wait_for_stability"
+             "  worst_snapshot=%f worst_stabilise=%f"
+             "  stable for %f thresh %f...\n",
+             worst_snapshot, worst_stabilise,
+             stable_for, threshold);
+      
+      if (stable_for > threshold)
+       break;
+    }
+    if (with_keypress)
+      with_keypress();
+    snapshot_idle();
+  }
+
+  if (it_took > worst_stabilise)
+    worst_stabilise= it_took;
+
+  free(last);
+  fprintf(stderr,"PAGING  wait_for_stability done.\n");
+}
+
+static void read_pages(void) {
+  CanonImage *current=0, *last;
+
+  raise_and_set_focus();
+
+  /* page to the top - keep pressing page up until the image stops changing */
+  wait_for_stability(&current,0, send_pgup);
+
+  /* now to actually page down */
+  for (;;) {
+    fprintf(stderr,"PAGING page %d\n",npages);
+    eassert(npages < MAX_PAGES);
+    page_images[npages++]= last= current;
+    send_pgdown();
+    wait_for_stability(&current,last, 0);
+    if (npages &&  /* first pagedown doesn't do much */
+       identical(current,last)) {
+      free(current);
+      break;
+    }
+  }
+  fprintf(stderr,"PAGING all done.\n");
+}    
+
 int main(int argc, char **argv) {
-  Window id;
-  CanonImage *ci;
+  screenshot_startup();
 
   id= strtoul(*++argv,0,0);
-  read_pages(id);
-  ci= screenshot_now(id);
+
+  read_pages();
   return 0;
 }
+